Polyamide 6,6: 1. During installation, avoid over-tightening and ensure there is adequate length allowance. Even if there is no relative movement between the high and low pressure ends, keep the high and low pressure by-passes loose. When the high and low pressure by-passes are compressed, changes in length and diameter occur, causing expansion under pressure and potentially reducing strength. 2. Avoid twisting the high and low pressure by-passes during installation. Even slight twisting may weaken them, leading to loose joints. 3. Do not let the high and low pressure by-passes come into contact with other hoses or piping to prevent wear and tear. In areas where the high and low pressure by-passes must cross or where friction with mechanical surfaces may occur, use protective devices such as high and low pressure by-pass clips or springs to prevent damage to the outer layer.